Cephalanthus occidentalis L.
Abstract
Buttonbush is a deciduous, wetland shrub or small tree that can reach 6 m in height but generally averages 1 to 3 m tall. The trunk base is often swollen. Branches are generally green when young but darken upon maturity and have conspicuous, raised lenticels. The short-petioled glossy green leaves are elliptic or lanceolate-oblong; they are mostly opposite but, on the same plant, can occur in whorls of three or four. Buttonbush is common along stream and pond borders, in swamps, floodplains and other riparian areas throughout the eastern half of the United States. It occurs naturally in southern Nova Scotia, New Brunswick, Quebec, and Ontario as well as through the eastern half of the Great Plains States; scattered populations and varieties are found in Arizona, New Mexico, southern California, and Texas. It also grows in Mexico, Cuba, Central America and in the West Indies. Buttonbush is a wetland species that cannot tolerate drought. It commonly grows in thickets in areas that have intermittent flooding. The open, rangy plant is not particularly attractive and is seldom found in cultivation today, although it was cultivated as early as 1735 as a honey plant. It is classified as a pioneer species and grows best in wet areas that receive full sun. It is able to tolerate some salinity that might result from hurricane storm surges but will not survive long-term exposure to salt water. . The creamy white summer flowers of buttonbush attract butterflies, honeybees, and hummingbirds. The flower balls stand on stalks that are 5 cm long. Flowers are produced over a long period, from late spring, throughout the summer months, and into early autumn. The long-stemmed fruits are clusters of achenes. The hard nutlets are 4 to 7 mm long and turn reddish-brown when mature. Buttonbush seeds are an important food for water birds but can be toxic to other animals. Buttonbush may also be propagated from tip cuttings in the spring or mature-wood cuttings in the winter.